“There’s noting sinister at all” in Courtier’s departure, she said, adding that the Post Office, which is going through radical change, has a 20% annual turnover of its approximately 200,000 staff.

Gregory added that the Post Office’s 15.6 billion pound (22.8 billion euro) pension fund is currently undergoing a “full actuarial evaluation”. She would not comment on the likely outcome of the review.

In December last year the Post Office said it would have to make an extra 330 million pounds of pension funding over the next two years due to market declines.